Traditional fixation devices, such as suture anchors or tissue anchors, are typically made of metal or hard plastic, and include a structure which connects or otherwise secures a filament, such as a suture, or a portion of tissue, to the body of the device. In certain applications, these devices have a diameter suitable to hold the devices within a bone. Such devices may also include additional structures to dig into the bone, such as wings, barbs, threads, or the like.
However, such traditional devices tend to be large in diameter, and must include sufficient material, or other additional structures, to withstand the forces pulling against the device, whether via a suture or directly against the device itself. The size of such devices may limit the possible implantation locations in the body, as sufficient bone mass is required to accommodate the device. Moreover, a large hole must be drilled into the bone to allow for passage of the device through the cortical layer and into the cancellous bone. The larger drill holes may be too invasive resulting in excessive loss of healthy bone, or creation of a large repair site.
A recent trend in fixation device technology is the “soft” device, also referred to as a “filamentary” fixation device, in which the device itself is constructed of a filamentary material. Such filamentary fixation devices may provide solutions to the various problems encountered with traditional devices, as summarized above.